The rollers in conventional overrunning roller clutches, especially those used at high speeds, are subject to pathway traction that can cause them to spin during clutch overrun. Furthermore, the rollers are guided basically just by the bumping contact that the roller ends make with the inside of the cage side rails. As such, the rollers are particularly subject to skew and misalignment at high speeds, and can wear on the side rails. Another problem with conventional roller clutches has been providing a secure retention for the rollers during shipping and handling. Typically, the roller energizing spring has been used to load the rollers against a roller retention groove in the cage. This presents the dilemma of either using an energizing spring that is just strong enough to provide roller energization, which gives a weak roller retention, or using a stronger roller energizing spring, which worsens the traction and roller spin problem.
Recent advances in roller clutch design by the assignee of the subject invention have provided a practical solution to all of the above problems in the form of a plurality of roller control cars, one for each roller. Each roller is pop fitted tightly and closely into a respective car, so that the cars stay with the rollers as the rollers travel. The roller cars, in turn, are guided by the clutch cage as they move, more rigorously than the roller ends alone would be guided by the cage side rails in a conventional clutch. The net effect is to keep the rollers square to the cage, very effectively preventing roller skew. Shipping retention can also be provided by releasably retaining the roller holding cars to the cage during shipping, the net effect of which is to retain the rollers to the cage, totally independently of the resilience of the energizing springs. In addition, the rollers are wrapped so tightly by the cars that a great deal of mutual friction is generated if the rollers tend to spin, retarding the speed of roller spin that would otherwise be generated, and producing frictional heat. In short, a great deal of advantage is gained with very little additional clutch structure. In the future, new roller cars will likely be invented tailored to specific and different and clutch environments and situations, or which provide new advantages in terms of of lower cost and easier assembly.